Crushing-mill



T. J. STURTEVANT.

v CRUSHING MILL.

APPLICATION FILED JUNE I5, 1917.

.1 360,466. Patented Nov. 30, 1920.

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CRUSHING MILL.

APPLICATION FILED JUNE I5. 1917.

,4 Patented Nov. 30, 1920.

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37 67 f OD-51 T. J. STURTEVANT.

CRUS'HING MILL.

APPLICATION FILED JUNE I5. 1917.

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I raven/$0? cfliiorney UNITCEDESTATESC "PATENT, OFFICE.

. THOMAS J. STURTEVANT, or WELLESLEY, MASSACHUSETTS, ASSIGNOR, BY MESNEASSIGNMENTS, TO STURTEVANT MILL COMPANY, 015 BOSTON, MASSACHUSETTS, A

CORPORATION OF MASSACHUSETTS.

CRUSHING-MILL.

Application filed June 15, 1917. Serial No. 174,875.

To all whom it may concern Be it known that I, THOMAS J. STURTE- VANT, acitizen of the United States, residing at lVellesley, county of Norfolk,and State of Massachusetts, have invented an Improvement in.CrushingMills, of which the following description, in connection withthe accompanying drawings, is a specification, like characters on thedrawings representing like parts.

The invention hereinafter described relates to crushing mills forreducing materials, of the general class shown in Letters Patent of theUnited States, No. 995,580, dated June 20, 1911; No. 1,000,457, datedAugust 15, 1911; and No. 1,105,713, dated August 4, 1914.

A mill of this class comprises a plurality of crusher rolls on'carriershaving arms projecting radially inward to engage a cen-' tral floatingwasher having a pivotal bearing on an adjustable pin carried by aspider, the arms of which are drawn inward toward the ring by helicalsprings.

The rolls, carriers, washer, spider and springs are all mounted on andsupported by a head or door which is hinged to the casing containing thering and rolls.

These mills experience very'heavy duty and sometimes operate under apressureof several tons. Consequently, the parts must be of massive,expensive construction.-

One of the objects'of the'prcsent invention is to reduce the number ofparts and the mass carried by the door, and provide a mill which issimpler, lighter and cheaper to manufacture than the mills shown in saidpatents. I

lVhen upper and lower crusher rolls are used, gravity tends to pull theupper roll away from the inner surface of the ring, while it tends topull the lower roll toward the ring. Heretofore, supplemental springs,

such, for example, as shown in the aforesaid Letters Patent, No. 1,105,?13, have been provided for the rolls to counteract the effect of gravitythereon.

Another object of the present invention is to provide meansforindependently varying the tension of the springs acting on the rolls,so that the pressure may be distributed to the rolls as desired, and thesprings for the rolls may be adjusted to compensate for the effect ofgravity thereon, and thereby eliminate the necessity for thesupplemental springs referred to.

Specification of Letters Patent. Patented 0V. 30, 1920.

Another object of the invention is to provide means for pressing therplls toward the ring, which will permit the door to be opened easilyand readily for the inspection of'the parts in the casing and the partscarried by the door.

Stillanother object of the invention is to provide simple and effectivemeans for ad-- justing the rolls toward or from the inner face of thering to take up wear on the parts and vary the distanceof the rolls fromthe ring as desired.

WVith the aforesaid and other objects in View, the characterof theinvention will be best understood by reference to the followingdescription. of embodiments thereof shown in the accompanying drawings,wherein I v Figure 1 is a side elevation of a "crushing mill shownherein as embodying the invention;

Fig. 2 is a vertical section through the mill shown in Fig. 1; Fig. 3 isa side elevation of the mill;

, Fig. 4 is a vertical section taken on line 44=.ofF1g. 2;

Fig. 5 is a vertical section of form of the invention; and a Fig. 61s aside' elevation of the mechanism shown in Fig. 5.

porting a casing 3 containing an anvil ring 5 having a concave innercrushing face 7.

This ring is mounted on a spider 9 having a hub 11 fast on a shaft 13journaled in bearings in standards 15 mounted on the basereferred to.The shaft hasa pulley 17 fast thereon whichmay be driven by a belt (notshown) from a suitable source of power.

One or more crusher rolls may be mounted within and cooperate with theanvil ring to crush material fed therebetween. In the.

present instance of the invention, three rolls 19 (Figs. 2 and 4) areshown having convex faces curved to conform to the concave face of thering. These rolls are ournaled on carriers, in the presentinstance ofthe invention, in the form of shafts 21 projecting laterally outwardfrom the casing and mounted in boss bearings 23 integral with yokes 25 amodified V I (Fig. 3) having ends journaled in bearings 27 mounted onthe outer face of a head or door 29 movable to open and closed positions. To permit this movement of the door, it may have hinged arms 31projecting therefrom above and resting on arms 33 integral with thecasing. A hinge pin 35 projects through registering holes in said arms.The door may be secured in closed position by screws 37 projectingloosely through ears on said door and threaded into similar ears 011said casing. One of these screws 37 may be longer than the others andproject through elongated slots in its ears and be threaded to a nut 37*set in a recess in the car on the casing to facilitate closing ofthedoor, as more fully hereinafter described. To facilitate opening ofthe door, a screw 39 may be provided threaded in an extension 41 of theear for the screw 37* and adapted to bear and react against an abutmenton the casing. The roll carriers pivotally mounted on the door asdescribed will permit the rolls to move toward and from the inner faceof the ring. Next will be described the means for pressing the rollstoward the ring. To accomplish this, each carrier may have an arm at?)(Figs. 1, 2 and projecting radially outward beyond the casing and havingits free end engaging the outer end of a pin 45, the inner end of whichis rounded and seated in the socket of a plunger l? in a cylinder 49mounted on the outer face of the'casing. .his plunger is pressed towardthe right of Fig. 2 by a helical spring 51 mounted in said socket. Thetension of said spring mayv be varied by a screw 58 threaded in an endof said cylinder and engaging a disk 55 bearing against the spring. Themovement of the spring toward the carrier-may be limited by a head 57detachably secured to said cylinder, and having a neck 59 projectingthere-- from to contribute to the support of the pin,

as more fully hereinafter described.

By the construction described, the helical springs will operate throughthe pins 5 and carrier arms 4-3 to rock the carriers and press thecrusher rolls outward toward the inner face of the ring. The springs maybe so adjusted thatwhen the material to be crushed is fed between thering and rolls, the latter will be moved inward away from the ring androck their carriers against their springs and compress the latter withthe tension required for producing efficient crushing pressure.

As stated, gravity tends to pull the upper roll away from the inner faceof thering. and tends to pull the lower rolls toward. said. face. Thescrew and disk for the spring of the upper roll may be adjusted to applya tension to said spring which is greater than the tension applied tothe springs for the lower rolls, and thus counteract the effect ofgravity on the. rolls ment of said. shaft will cause the eccentricportions to present their rolls nearer to or 7 5 farther from the ringas required. To secure the shafts in their different positions ofrotative adjustment, each bearing may be provided with a'key 61 (Figs. 2and 3) adapted to enter any of the key slots 63 distributed at intervalscircumferentially of the shaft. The key may be held to prevent itssliding axially of the shaft by a set screw 65.

The carriers project through elongated openings 67 (Fig. 2) in the headto allow the rocking of the carriers. To prevent'escape of dust from thecasing through said openings they may be covered by guard plates 69movable with the carriers.

The material to be crushed may be fed into the mill through the usualhopper 71 (Fig. 1) and a spout 73, the latter being mounted on the doorand directing the material to the inner surface of the ring.

hen it is desired to inspect or repair the parts within the casing andthe parts carried by the door, the latter is swung on its hinges to itsopen position. To accomplish this, the screws 37 are released and thenthe opening screw 39 is adjusted to force the door ajar. Then the doormay be swung to its open position, and in the course of this movementthe carrier arms will move. automatically away from the spring-pressedpins 45. After the rolls have moved away from the ring, they may dropdownward until their carriers are limited by the lower ends of theelongated slots in the door.

\Vhen it is desired tov close the door, it may be swung on its hingesback toward the casing, and in the course of this movement the carrierarms will automatically come into engagement with the pins L5, therebyrocking the rolls outward toward the die to their operative position.The screw 87 re ferred to is of sufficient length to catch into threadedengagement with the nut 37 before the rollsv are moved outwardly asdescribed. This screw may be tightened and will afford sufiicientmechanical advantage to complete the closing movement of the door, andthereby rock the roll carriers away from the ends of the slots in thedoor supporting them while the door is open.

In the modification shown'in Figs. 5 and 6. a somewhat differentmechanism is provided for pressing the crusher rolls outward toward thedie. Each carrier is pivotally connected to a yoke 75 having an adustlngscrew 7! bearing on the outer free end of an arm 7 9 pivoted on abracket 81 on a plate 82- mounted on the casing. The arm is urgedoutwardly by a helical spring 83 confined between socket 85 on the armand the outer face of said plate. To limit outward movement of said arm,a belt 87 may be provided having a head seated in a recess beneath aboss 89 on said plate, said bolt pro ecting upward through said springand mit the okes to be rocked outwardly away from the arms 79. Then thedoor may be swung on its hinges to its open position as.

described. The door may be closed as before, and then the yokes areswung inward to the free ends of the arms, and the screws '77 aretightened sufficiently to return to their original positions ofadjustment. The adjusting screws 77' and 87 may be set in differentpositions to vary the effective ten sion of the springs on the rolls asdesired.

It will be observed that by the constructions described the door isrelieved from the burden of supporting the springs, the heavy spider andthe washer which are mounted on the door in the mills shown in theaforesaid patents. Also, this permits the carriers and the door to be oflighter simpler construction. In fact, the entire organization may be ofa lighter, simpler construction, the parts of which are cheaper tomanufacture and easier to assemble and operate.

I It will be understood that the invention is not limited to thespecific embodiments shown, but that various deviations may be madetherefrom without departing from the spirit and scope of the appended.claims.

Claims.

1!... In a crushing mill, the combination of a casing, a head thereonmovable to open and closed positions, hinge means connecting said headwith said casing, an anvil ring mounted in said casing, a plurality ofcrusher rolls opposed to the inner face ott said ring, carriers for saidrolls pivotally mounted on and supported by said headto swing with thelatter as it moves to open and closed positions, and spring-pressedmembers mounted on said casing, acting on said carriers to press saidrolls toward said ring, said spring-pressed members and car riers havingprovision for automatically separating on movement of said head to openposition, and for automatically operatively engaging on movement of saidhead to closed position.

2. In a crushing mill, the combination of a casing, a head thereonmovable to open and closed positions, hinge means connecting said headwith said casing, an anvil ring; mounted in said casing, a plurality ofcrusher rolls opposed to the inner face of said ring, carriers for saidrolls pivotal'ly mounted on and supported by said head to swing with thelatter as it moves to open and closed positions, andspring-pressedmembers mounted on said casing, acting on said I carrierstopress said rolls toward said ring, said carriers being movable toengage and automatically tension said spring-pressed membersv on closingmovement of said door.

8. In a crushing mill, the combination of a'casing, a head thereonmovable to open and closed positions, hinge means connects ing said headwith said casing, an anvil ring mounted in said casing, a plurality ofcrusher rolls opposed to the inner face of said ring, carriers for saidrolls pivotally mounted on said head and having outwardly projectingarms, members mounted on said casing adjacent said arms, and springs forpressing said members toward said arms to move the rolls toward saidring, said arms being movable on opening movement of said head to reducetension on said springs and then separate from said members. 7

4. In a crushing mill, the combination of a casing having a door hingedthereto adapted to swing to open and closed positions, an'anvil ringmountedin said casing,

a carrier pivotally mounted on said door having a shaftprojectingintosaid casing, and an arm projecting outwardly externally of said casing,a'roll on said shaft for cooperation with said ring to reduce materialsfed between them, a member mounted on said casing adjacent said arm, andspring means for pressing said member into engagement with said armtomove said roll toward said ring, said arm being automati cally movableinto and out of engagement with said member incidentally to closing andopening movements of said door.

5. Ina crushing mill, the combination of a casing, a cylinder mountedthereon, a pin projecting outwardly from one end of said cylinder, acoil spring mounted in said cylinder for pressing said pinoutwardlythrough said end, a door hinged to said cas ing, an anvilring mounted insaid casing. a carrier pivotally mounted on said'door and 'movabletherewith, and a roll on said carrier cooperating withsaid ring toreduce THOMAS J. STURTEVANT,

